Robert A. Bartlett Jr. explains why a world-class collection of trees needs state-of-the-art irrigation.

My decision to transform the R.A. Bartlett Research Laboratories and Arboretum into the living museum that exists today was centered on the need for water. My father, Robert Bartlett Sr., purchased the property in 1965, a few years after he became president of the family business, Bartlett Tree Experts. He intended for the 350-acre property, nestled in the rolling hills outside of Charlotte, North Carolina, to serve as a research laboratory and training center for the growing company.

To that end, the company established facilities and plots where staff scientists conducted experiments on plant care and pathology. Previously, this work had been performed in Stamford, Connecticut, where my grandfather had set up our first tree research laboratory and training facility in 1913. A portion of the original site still exists today as the Bartlett Arboretum and Gardens, although it has no affiliation with the company.

Previously, the Charlotte property had been a working horse farm with large fields and pastureland. When my father acquired the land, he planted azaleas (Rhododendron) and hollies (Ilex), along with other plants that form the basis of the collections we have today. In those early years, I remember seeing young trees begin to establish themselves and rise above the forage grasses.

The climate near Charlotte allowed the cultivation of species common in both northern and southern gardens, which was important since we had field offices throughout the United States (and now Canada, the United Kingdom, and Ireland). Still, the summers in Charlotte are hot and humid. To maintain the collections, we pumped water from one of three existing ponds to provide irrigation, but at first, the capabilities were technologically limited. The earliest systems consisted of gasoline-powered pumps sitting on the shore of the ponds and serving manually operated spigots. Remnants of those systems can still be found on the property, and portions of their piping are still in use today.

During the first thirty years in our Charlotte location, it was apparent that some of the plants were beginning to suffer from our limited irrigation capabilities. In particular, the collection of azaleas that my father had started planting on an eighty-foot hill, now affectionately called Rhodie Hill, required extensive watering. In midsummer, it was challenging to stay ahead of the heat, especially because the water had to be manually hauled up the paths that wind around the hill.

The impact of a changing climate also became more apparent at this time. When my father bought the land, the property was categorized by the US Department of Agriculture as being in plant hardiness zone 7 (meaning the average minimum temperatures fell between 0 and 10°F); however, it is now considered zone 8 (averaging between 10 and 20°F). Due to changes in the weather patterns, longer dry periods developed, and more dramatic swings in rainfall became the new normal. It was clear that we could no longer sustain our collections without investing in a state-of-the-art irrigation system.

After my father passed away in 1998, we began to make a significant investment to help maintain and develop the property. It would continue to serve as a research station and laboratory, complete with a training facility for clients and arborists and a diagnostic clinic where our researchers process thousands of plant and soil samples sent by our field offices. At the same time, we were determined to continue building the collections into a world-class arboretum. With this goal in mind, we decided to put in an irrigation system that could provide consistent water to the growing collections.

We installed a new distribution system to feed the early network of pipes and facilitate manual watering capability in adjoining areas. Most importantly, the system directed a large volume of water to one of our ponds. Now, with the ability to keep a single, large reservoir of water full at all times, the Research Lab and Arboretum was primed for much more extensive, and automated, irrigation operations. In 1999, we began installation of the first automated system. It allowed us to direct a precise amount of water overnight to specific areas on the property. The collections grew like never before. The system also made new locations available for dedicated research plots. Automatic irrigation was a game changer.

Today, the collections are expansive, consisting of over twenty-six thousand accessioned plants.

At that point, we began to strategically build our collections. We launched collaborations with other arboreta and research institutions across the globe and started adding to the diversity of our cultivated plants. Today, the collections are expansive, consisting of over twenty-six thousand accessioned plants in fourteen major groups. We have one of the largest collections of holly in the United States, along with extensive collections of elm (Ulmus), crape myrtle (Lagerstroemia), maple (Acer), witch-hazel (Hamamelis), linden (Tilia), and boxwood (Buxus). Seven collections are accredited through the Plant Collections Network, including the largest collection of Magnolia cultivars in the world.

Among the collections, those which were established early and added on to over the years continue to be among the most satisfying for me to watch through the year. Our main grouping of magnolias borders Youngblood Road, a two-lane highway that passes the arboretum. When you drive around the corner and see the magnolias in bloom, the sight of the different colors almost takes your breath away. There is just about every shade and hue of purple, pink, white, and yellow that you can imagine. Rhodie Hill is another favorite. The hill comes alive in a kaleidoscope of spring color, and with mature specimen trees overhead, the winding paths offer beautiful surprise around every corner.

We have now begun focusing on wild-collected plant material, especially prioritizing species of conservation concern. One of the plants that we are playing a role in conserving is a rare North American species known as the pyramid magnolia (Magnolia fraseri var. pyramidata). In an effort to understand the distribution of this species and increase documented holdings in cultivation, our arboretum has partnered with The Morton Arboretum, the University of Florida North Research and Education Center, the Chicago Botanic Garden, the Atlanta Botanical Garden, and the US National Arboretum to scout populations, assess their health, and collect seed (when present) for propagation and distribution. Through collaborative efforts like this, and with other strong networking partners such as the Arnold Arboretum, Longwood Gardens, and many others, we have made conservation of rare species a new part of our mission.

Looking at all the natural beauty established here, visitors may find it easy to forget that this is a relatively young arboretum. We pride ourselves on the ability to adapt with the times and use our natural water resources to maintain the vitality and health of our collections. The key and catalyst to our success has been access to water and having the irrigation needed to help the plants thrive. Without it, we could not have created this botanical wonderland in such a short amount of time.

Robert A. Bartlett Jr. is the chairman and chief executive officer of Bartlett Tree Experts.

From “free” to “friend”…

Established in 1911 as the Bulletin of Popular Information, Arnoldia has long been a definitive forum for conversations about temperate woody plants and their landscapes. In 2022, we rolled out a new vision for the magazine as a vigorous forum for tales of plant exploration, behind-the-scenes glimpses of botanical research, and deep dives into the history of gardens, landscapes, and science. The new Arnoldia includes poetry, visual art, and literary essays, following the human imagination wherever it entangles with trees.

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